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Reductions of aldehydes and ketones with a readily available N-heterocyclic carbene borane and acetic acid.

ABSTRACT: Acetic acid promotes the reduction of aldehydes and ketones by the readily available N-heterocyclic carbene borane, 1,3-dimethylimidazol-2-ylidene borane. Aldehydes are reduced over 1-24 h at room temperature with 1 equiv of acetic acid and 0.5 equiv of the NHC-borane. Ketone reductions are slower but can be accelerated by using 5 equiv of acetic acid. Aldehydes can be selectively reduced in the presence of ketones. On a small scale, products are isolated by evaporation of the reaction mixture and direct chromatography.

SUBMITTER: Lamm V

PROVIDER: S-EPMC3629027 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Reductions of aldehydes and ketones with a readily available N-heterocyclic carbene borane and acetic acid.

Lamm Vladimir V Pan Xiangcheng X Taniguchi Tsuyoshi T Curran Dennis P DP

Beilstein journal of organic chemistry 20130408

Acetic acid promotes the reduction of aldehydes and ketones by the readily available N-heterocyclic carbene borane, 1,3-dimethylimidazol-2-ylidene borane. Aldehydes are reduced over 1-24 h at room temperature with 1 equiv of acetic acid and 0.5 equiv of the NHC-borane. Ketone reductions are slower but can be accelerated by using 5 equiv of acetic acid. Aldehydes can be selectively reduced in the presence of ketones. On a small scale, products are isolated by evaporation of the reaction mixture a ...[more]

PMID: 23616812

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